There are many excellent PS(Adobe Photoshop) tutorials to learn. Here are some popular online course platforms and course recommendations:

1. Udemy: Udemy is a popular online learning platform, which provides various PS tutorials. Recommended courses include "Adobe Photoshop CC-Basic Introduction" and "Adobe Photoshop CC Complete Training Course".

2. Lynda: Lynda is a well-known online learning platform, which provides a large number of tutorials related to design and creativity. They provide many noteworthy PS tutorials, such as "Photoshop CC 2121 Basic Training" and "Photoshop CC 2121 Advanced Training".

3. YouTube: There are many free PS tutorials on YouTube. You can search and watch video tutorials provided by professional designers and educators. Some popular channels include "PHLEARN", "Tutvid" and "Adobe Photoshop".

whether you are a beginner or an experienced user, these courses will help you improve your PS skills and learn how to use various technologies and tools. Please choose the course that suits you according to your needs and interests.